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Archive for 'November 2013'

In this age of rising health care costs, researching simple and
effective means to prevent prolonged hospital stays is a priority. The
past decade has seen increasing interest in the role that vitamin D
plays in the immune system. Quraishi and
co-workers recently published some results of a retrospective
analysis into vitamin D levels before bariatric surgery and the risk
of infection after the operation.

As our understanding of human genetics has grown, we are starting to
appreciate the effect of how genes and environment interact.
Researchers Shaghaghi
and associates published an article on the effect that
variations in a vitamin C transporter have on two forms of
inflammatory bowel disease. Vitamin C is a major water-soluble
antioxidant. It has been shown to reduce inflammation by scavenging
reactive oxygen species to prevent cellular damage according to a
review by Traber
and Stevens. Buffinton and
Doe found that levels of vitamin C were lower in people with
inflammatory bowel disease, and this could hinder recovery of the
intestinal lining.

Have you ever kept a diet
record or filled in a dietary
questionnaire? Was it accurate? Did you forget to include
something that you ate? Did you change your diet to make it seem like
you eat healthier than you normally do? These are some of problems
that make accurate assessments of food and nutrient intakes
difficult. Last month, Archer
and colleagues reported results of an analysis of
under-reporting in the NHANES nutrition survey.
There has been a recent reply by Mitka.
TalkingNutrition provides a perspective on this issue, and how it
relates to nutrient intakes.

Cataract is the worldwide leading cause of visual impairment, being
responsible for a little under half of all cases according to the World
Health Organisation. Cataract develops when the lens in the eye
is damaged over time, and risk factors include older age, cigarette
smoking and exposure to UV light. Although cataract can be treated
surgically, there are barriers that prevent access in many countries.
People also may suffer from impaired vision for years before they are
treated for the condition. How can risk of cataract be reduced, and is
there a role for antioxidants?

Food consumption data is valuable for many reasons. As the CDC
notes, the data is used nutrition monitoring and surveillance and
a variety of policy making and research purposes, including dietary
guidance, food fortification, environmental exposure assessment, and
nutrition assistance and education program planning and evaluation.
The USDA has invested in the collection of national food consumption
data for >70 years. The National Health and
Nutrition Examination Survey (NHANES) is the primary instrument
used to nationally assess the health and nutritional status of Americans.

Using cross-sectional data, Deierlein and colleagues assessed
nutrient intakes and Healthy Eating Index (HEI) scores of 1,306 New
York City adults living independently (60-99y)

Food fortification has been credited with helping to avoid widespread
vitamin and mineral deficiencies in millions of people over the past
decades. The reason why fortification is so effective is that it has
the potential to increase the nutrient levels within an entire
population without requiring any behavior change on the part of the
individual. Fortification may be particularly helpful to increase the
supply of nutrients that are only found in a limited number of foods,
or restricted within a few food groups. Vitamin D has been added to
milk in the United States and Canada since the 1940s, and the
introduction of a carefully-planned fortification policy has been
credited with eliminating rickets as a public health issue (the
National Academies Press has a summary of fortification programs in
the US and Canada here).

Other countries do not fortify with vitamin D. As vitamin D
fortification is not allowed in Germany, yet the adult population
appears to have generally low
vitamin D levels compared to the US, Brown and
colleagues have modeled the effect of fortifying various carrier
foods with vitamin D

Telomeres are repeated nucleotide sequences which protect chromosomes
during cell replication. In cell division, chromosomes are ‘read’.
Having telomeres at the end to ensure the entire gene is transcribed.
Similar to having an extra-long zipper in a coat which guarantees the
full length of the coat is zipped up. Because some of a telomere may
not get copied during replication, telomere regions become shorter as
animals age. Shorter telomeres are associated with accelerated aging
(Gasser
& Coutre, 2013).

Suboptimal nutrition and stress contribute to accelerated aging (Aiken et al,
2013). In a new study

Yesterday, TalkingNutrition
reported on how an adequate vitamin B12 status can improve health
outcomes for babies during their first thousand days from conception
to two years of age. Today, an article on the link between high
vitamin B12 levels and cancer risk by Arendt
and colleagues has been picked up as a nutrition news story by
various online news providers. What is going on here?

Folic acid status is especially important for women during pregnancy
and to maintain healthy homocysteine levels (a risk factor for
cardiovascular disease) throughout life. Changes in folate assessment
methods have made it difficult to compare data (Pfeiffer
et al, 2010) and to reliably quantify dietary folate
recommendations for optimal health.

Duffy
and colleagues conducted a dose-response meta-analysis in
healthy adults to quantify the relationship between folic acid intake
and folate biomarkers.

The CDC
reports on four cases of vitamin K deficiency bleeding (VKDB)
in infants aged 6 to 15 weeks in a Tennessee children’s hospital. VKDB
condition is actually preventable, but why does it happen, what can be
done about it, and why would some infants not receive preventive measures?

Did you know that low serum vitamin E concentrations could lead to
bone loss and muscle wasting? Probably not but new data from the
Swedish Mammography Cohort (SMC) and the Uppsala Longitudinal Study of
Adult Men (ULSAM) finds that low serum concentrations of α-tocopherol
are associated with an increased risk of fracture in elderly men and women.

Swedes, like many others, do not consume recommended amounts of
vitamin E. Because an increase in oxidative stress with aging leads
to age-related bone loss and muscle
wasting (sarcopenia), inadequate vitamin E status is a health concern.

Preterm birth affects around 10% of all births in the world,
according to the World
Health Organisation, and is a large contributor to poor
infant-related outcomes. Not only are newborns at increased risk of
illness because they have not had enough time to develop fully before
they are born, the third trimester of pregnancy is also a time during
which the greatest proportion of nutrients such as calcium, iron
essential fats and the fat-soluble vitamins are transferred to the
fetus. Vitamin E is one of those nutrients that is found in low levels
in preterm infants. Researchers are interested in whether a simple
treatment such vitamin E supplementation can help improve health
outcomes in preterm infants.

Two trials found a small, borderline-significant benefit from
multivitamin supplements on cancer in men only and no effect on CVD.
So reads the conclusion by Fortmann and
colleagues after systematically reviewing studies on multivitamin
use by community-dwelling, nutrient-sufficient adults. What does this
mean? What about women?

Cancer and cardiovascular disease are complex non-communicable
diseases. Prevalence is attributable to many environmental and
lifestyle influencers, including multiple nutrients – amount and type
of fat consumed, vitamins, alcohol intake, etc. Using studies
primarily conducted in men (because there weren’t many involving
women), the most promising results came from 2 multivitamin trials
using a wide variety of nutrients at physiological doses.

Over the weekend, reports came through about the rise of rickets in
the UK over the past few years . The UK’s chief medical officer
Professor Dame Sally Davies included recommendations to provide free
vitamin supplements to all children under the age of five in her
report “Our
Children Deserve Better: Prevention Pays”. Her recommendations
are based on surveys of vitamin D status in children that have shown a
sizeable increase in rates of vitamin D deficiency and rickets

Nutrition is confusing. It is frustrating too because we really don’t
know our nutrient status unless we get a blood test. The most recent
National Health and Nutrition Examination Survey (1999-2006)
using blood lab tests reports that the prevalence of nutrient
deficiencies hasn’t changed for vitamin B6, iron, vitamin D, vitamin
C, vitamin B12, vitamin A, vitamin E and folate. Without this
information, how does one know if they should be using dietary
supplements? To answer this question, let’s examine the practices of
health professionals.

If you search google with the term ‘antioxidants’, one of the first
links is MedlinePlus which states:

Antioxidants are substances that may protect your cells against the
effects of free radicals. Free radicals are molecules produced when
your body breaks down food, or by environmental exposures like
tobacco smoke and radiation. Free radicals can damage cells, and may
play a role in heart disease, cancer and other diseases.

No mention of antioxidants and hearing loss. So it was
interesting to see the article by Choi
and colleagues linking antioxidants with a risk of hearing loss.

The number of people with asthma in the US is growing every year. According to
the CDC, roughly 25 million Americans have asthma, half of whom
have had an asthma attack in the past year. Asthma
is more prevalent among the poor and African Americans,
Hispanics and Puerto Ricans than Caucasians. Worldwide, 235 million
people have asthma. It is the most common chronic disease among
children (WHO, 2011).

Asthma is caused by a combination of genetic and environmental
factors. One protective factor seems to be vitamin E, possibly because
most people - especially children, young adults, non-Hispanic Blacks
have low blood α-tocopherol levels